Engineer s brake-valve



(No Model.) 2 Sheets- Sheet 2. I W. T. BOTHWELL. ENGINEBRS BRAKE VALVE UNITED STATES PATENT ()FFIQE.

WILLIAM T. BOTHWELL, OF JERSEY CITY, NEW JERSEY.

ENGINEERS BRAKE-VALVE.

SPECIFICATION forming part of Letters Patent No. 508,365, dated November '7, 1893.

Application filed June 29, 1893. Serial No. 479,133. (No model.)

To all whom it may concern.-

Be it known that I, WILLIAM T. BOTHWELL, a citizen of the United States, residing at J orsey City, in the county of Hudson and State of New Jersey, have invented certain new and useful Improvements in Engineers Brake- Valves, and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in engineers brake valves or that class of valves which'are employed in the cabs of locomotives to enable the engineer to effect communication between a main air reservoir and a train pipe and between the train pipe and an exhaust port and thereby manipulate the brakes; and it'has for its general object to provide a brake valve adapted to be employed in conjunction with pneumatic brake systems such as at present in general use, and one which will enable the engineer to apply the brakes quickly as in making an emergency stop or slowly and gradually to make a service stop, as desired.

With the foregoing end in view, the invention will be fully understood from the following description and claims when taken in connection with the annexed drawings, in which- Figure 1, is a perspective view of my improved device with the exhaust, the train or line pipe, and the pipe for connecting with the main reservoir, partly broken away. Fig. 2, is ahorizontal, sectional view of the same. Fig. 3, is a vertical, sectional view, through the valve casing and a part of the exhaust pipe, illustrating the valve in elevation. Fig. 4, is a perspective view of the valve removed with the operating handle attached. Fig. 5, is a horizontal sectional view, illustrating the valve turned in a position to let air pass from the main air reservoir into the train pipe so as to release the brakes, and Fig. 6, is a similar view illustrating the valve turned so. as to bring the small passage into communication with the train pipe and the exhaust and let the air pass slowly from the train pipe so as to effect a slow or gradual application of the brakes.

Referring by letter to said drawings: A,

indicates the valve casing. This casing is provided with a central, vertical, tapering or conical bore a, to receive the plug or valve. The casing A, is provided at diametrically opposite points with ports or apertures b, c, and communicating with these ports are enlarged epertures which are screw-tapped as shown at d, and e, which receive the externally-threaded ends of the pipes B, and C. The pipe 0, is the exhaust pipe and the plpe B, is designed to connect with the train or line pipe, which leads to the brake mechanism, which latter may be of any approved construction, such as at present in general use. The valve casing is furthermore provided 1n one side at a suitable point between the ports b, o, with a port or passage f, which also communicates with an enlarged aperture D,which is internally-screw threaded to receive the externally-threaded end of the pipe E, which is designed to connect with the main air reservoir or source of supply.

F, indicates the valve. This valve is of a conical form'so as to bear snugly in the conical bore of the casing and it is held within the casing by means of the washers h, and v. and the headed screw g or other suitable fastening devices. This valve which is provided at its upper end with a'suitable handle G, is provided about midway of its length, or at a suitable point therein,with a transverse supplypassage H, and at one end of this supply passage, a recess is, is formed on the outer s1de of the valve, for a purpose which will presently appear. Leading from this supply passage H, is a portor passage I, which communicates with the supply passage H, obliquely, as shown. It will be observed that in Fig. 5 the recess k, and the port or passage 1, have communication with the main supply passage.

I, indicates a small passage which extends diametrically through the valve, and 1n a plane relatively at right angles to the supply passage H, and crosses the latter but is free from communication therewith, as shown. This passage I, is preferably obtained by the employment of the tube K, inserted in a hole or aperture in the valve. The handle G of the valve is provided with a spring stop L, and the body of the valve casing is provided with studs or lugs M, to limit the range of movement of the handle, and the valve casing is provided between these studs or lugs, with recesses or notches m, n, p, and q, to receive the spring L', so that the handle may be secured in the desired position in the turning of the valve.

In Fig. 1, of the drawings, I have illustrated the handle in the position which it assumes when the valve is in the position shown in Fig. 2, with the main supply passage H, connecting the exhaust pipe 0, and the train or line pipe B. When thus placed, the valve will permit a large volume of air to pass from the line or train pipe to the open air so as to reduce the pressure in the train pipe below that in the auxiliary reservoir or reservoirs (embodied in the usual brake systems) and quickly and powerfully apply the brakes and make a quick or emergency stop. When the handle is moved so that the spring will engage the notch or recess 19, the valve will be in the position shown in Fig. 5, so as to effect communication between the train pipe and the main air reservoir pipe E, and let a head of air pass from the main air reservoir to the train pipe and release the brakes. When the handle is moved to the next notch 11., the valve will be entirely closed, and when it (the handle) is moved to the notch w, the valve will assume the position in Fig. 6, and the small or minute passage I, will efiect com munication between the pipes O, and B, and will allow a small volume of air to pass from the train pipe to the open air so as to apply the brakes slowly and gradually as in making a service stop.

The normal running position of the valve is shown in Fig. 5, the handle G, beingin engagement with the notch 19. Now it will be seen that if the engineer desires to make a quick or emergency stop, it is only necessary for him to move the handle to the notch q, when the passage H, will efiect communication between the pipes C, and B, and will permit a large volume of air to rush from the pipe B, so as to quickly reduce the pressure therein and apply the brakes. With the valve in its normal running position and the handle G, in engagement with the notch 19 when the engineer desires to make a gradual or slow service stop it is only necessary for him to move the handle to the notch m, when the minute passage I, will efiect communication between the pipes C, and B, and will permita small volume of air to pass from the train pipe to the open air for the purpose before described.

Having described my invention, what I claim is- 1. In an engineers brake valve for pneumatic brake systems, the combination witha valve casing, having the three ports or passages, as described, of a plug or valve arranged in the casing, and having the main supply passages, the port or passage connected with the main supply passage and also having the recess leading from the main supply passage and the port or passage free from communication with the other ports or passages of the valve, and adapted to connect the exhaust port or passage of the valve casing with the passage which receives the train or line pipe, substantially as specified.

2. In an engineers valve for brake systems, the combination with a valve casing constructed as described, and having a conical bore, of a plug or valve arranged in said bore and carrying an operating handle, said valve having a main supply passage extending diametrically through it, and a smaller passage extending diametrically and relatively at right angles to the main passage and free from communication therewith and also having a port: or passage leading from the main supply passage, substantially as specified.

In testimony whereof I affix my signature in presence of two witnesses.

WILLIAM T. BOTHWELL.

Witnesses:

K. F. MATTHEWS, CHAS. W. BLACKWOOD. 

